Luck gives small bonuses to many combat attributes. Unlike other attributes, Luck is not shown on your character sheet, and is a 'hidden' attribute.
The default value for Luck is 50. Gains per point above 50:
Accuracy: 0.40 Defense: 0.40 Critical hit chance: 0.30 Physical save: 0.175 Mental save: 0.175 Spell save: 0.175
(i.e. The default 50 Luck gives no benefit, and you will get a penalty at less than 50 Luck.)
In addition, each point above 50 gives a 0.2% chance to avoid your own AoE effects (similar to Spellcraft), and if you know (note: only found on NPCs), increases the chance to not break stealth by 0.2%. The Defense given by is proportional to your Luck.
Luck also has a few more minor effects:
- Luck does not affect the chance to get a hostile encounter on the world map (which is always 2%), but if you do not get a hostile encounter, the chance of getting a harmless encounter is 1% + (Luck * 0.07%).
- The chance to be able to apologise to Ukllmswwik the Wise (and avoid fighting him) if you tell him you spoke with Slasul is (30 + Luck)%.